Root canal treatment or endodontic treatment, is a common procedure in dentistry. The main indications for root canal treatment are irreversible inflammation of the dental pulp (pulpitis) and death of the dental pulp caused by carious processes, tooth cracks or chips, or dental trauma. Successful root canal treatment is characterised by an absence of symptoms and clinical signs in teeth without radiographic evidence of periodontal involvement. The success of root canal treatment depends on a series of variables related to the preoperative condition of the tooth, as well as the endodontic procedures.
I am not an endodontist but the diagnosis matters and determines the number of visits required.
According to many studies, there is no significant difference single visit and multiple visits. Therefore, I prefer to finish my cases in one visit unless I could not do that due to complications, time and etc..